Radiocarbon dating of groundwater has been used to delineate flowpaths and calculate
hydraulic conductivity as part of a detailed hydrogeological/hydrogeochemical study
of the Tullaroop catchment in the Upper Loddon, central Victoria. The dating
confirms that both the basalt and deep lead aquifers in the study area are recharged
through scoria cones at volcanic eruption points. The radiocarbon dating also shows
that flow paths in the basalt aquifer are complex since ages do not always increase
downflow; any hydraulic conductivity calculations must take this into account. One
anomalously old 14C date supports other hydrogeological evidence that suggests
groundwater in the deep lead is trapped upflow of horsts created by ENE Cainozoic
faults.